000 AXNT20 KNHC 041205 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 805 AM EDT Wed Jul 4 2018 Tropical Weather Discussion for North America, Central America Gulf of Mexico, Caribbean Sea, northern sections of South America, and Atlantic Ocean to the African coast from the Equator to 32N. The following information is based on satellite imagery, weather observations, radar and meteorological analysis. Based on 0600 UTC surface analysis and satellite imagery through 1130 UTC. ...TROPICAL WAVES... An Atlantic Ocean tropical wave is along 32W/34W, from 16N southward. A 1010 mb low pressure center is along the wave near 10N. Widely scattered to scattered moderate and isolated strong rainshowers cover the area that extends from 12N southward between 30W and 40W. An eastern Caribbean Sea tropical wave is along 62W/63W from 18N southward. Precipitation: widely scattered moderate to isolated strong rainshowers cover the area that extends from land to 17N between 65W and 70W. A western Caribbean Sea tropical wave is along 82W/83W from 23N in Cuba southward. Broad cyclonic wind flow exists at 500 mb and 700 mb, from 20N southward between 80W and Central America. Precipitation: widely scattered to scattered moderate to strong rainshowers cover the area that extends from 20N southward between 80W and 86W, including in coastal areas of Honduras and Nicaragua. ...MONSOON TROUGH/ITCZ... The monsoon trough passes through the coastal areas of Guinea- Bissau near 12N16W to 10N34W and 05N40W. The ITCZ continues from 05N40W to 05N47W, and 07N58W at the coast of Guyana. Precipitation: widely scattered moderate to isolated strong rainshowers from 06N to 12N between 11W and 23W, elsewhere from 12N southward between 26W and 50W, and from 11N southward between 50W and 60W. ...DISCUSSION... GULF OF MEXICO... A trough extends from a 1014 mb low centered in southern Louisiana near 30N92W to 28N89W to 25N90W. Widespread showers with embedded tstms are noted N of 26N and W of the trough to about 94W. Lightning density indicates frequent lightning with much of the observed convection, more concentrated now over the upper Texas coast. This convective low pressure system will continue to enhance showers and thunderstorms system across the northern Gulf states from southern Mississippi to SE Texas today. Widespread showers and embedded thunderstorms from a low centered near 28N93W will slowly move westward into NE Texas later today. A weak ridge over the remainder of the Gulf will persist through Sat night. A surface trough will emerge off the Yucatan Peninsula each evening, and enhance nocturnal winds over the SW Gulf through Sun. CARIBBEAN SEA... Please read the TROPICAL WAVES section for information about the two tropical waves that are in the area. The 82W/83W tropical wave will continue moving westward into Central America through Thu. The 62W/63W tropical wave will reach the western Caribbean on Fri. Winds will approach gale force near the coast of Colombia, mainly at night, tonight through Fri night. A vigorous tropical wave in the eastern Atlantic will reach the tropical N Atlantic around Sat night. ATLANTIC OCEAN... A surface trough extends from 32N78W to 24N79W. Scattered showers and isolated tstms are observed ahead of the trough axis forecast to move west into Florida through tonight. An area of cloudiness and showers remains a few hundred miles southeast of Bermuda. Although this disturbance is currently disorganized, environmental conditions could become more conducive for a low pressure system to form by late this week in the area southwest of Bermuda. The system is then forecast to move generally northward over the weekend and begin interacting with a frontal system on Sunday, which would limit any additional development. Surface high pressure of 1032 mb located W of the Azores near 37N39W extends a ridge across the remainder of the central and eastern Atlantic forecast waters. Moderate to fresh trade winds are noted along the southern periphery of the ridge, which reaches the NE Caribbean. An upper level cyclonic circulation center is near 29N74W, about 240 nm to the NNE of the NW Bahamas. Upper level cyclonic wind flow that is moving around the 29N74W center covers the Atlantic Ocean and the Gulf of Mexico from 23N northward between 65W and 85W. A surface trough is along 32N71W 28N75W 24N77W in the Bahamas. Precipitation: isolated moderate to locally strong rainshowers cover the Gulf of Mexico and the Atlantic Ocean from 20N to 32N between 65W and 86W. Widely scattered moderate to isolated strong rainshowers are in the Atlantic Ocean from 24N northward between 57W and 65W. A second upper level cyclonic circulation center is near 31N48W. Precipitation: isolated moderate to locally strong rainshowers are from 29N to 33N between 46W and 55W. A surface trough extending across the Bahamas will move west into Florida through tonight. A second trough will develop near Bermuda tonight, then shift NW of the area by Fri. High pressure will build across the region through the weekend. Winds N of Hispaniola will pulse to strong each afternoon and evening the remainder of the week. The current 32N71W 28N75W 24N77W surface trough will move across the NW Bahamas and over Florida on Wednesday and Wednesday night. High pressure will build in its wake. The wind speeds to the N of Hispaniola will pulse to strong each day during the afternoon and evening beginning on Wednesday. A trough extends from a 1014 mb low centered in southern Louisiana near 30N92W to 28N89W to 25N90W. Widespread showers with embedded tstms are noted N of 26N and W of the trough to about 94W. Lightning density indicates frequent lightning with much of the observed convection, more concentrated now over the upper Texas coast. This convective low pressure system will continue to enhance showers and thunderstorms system across the northern Gulf states from southern Mississippi to SE Texas today. The remainder of the Gulf remains under the influence of a weak ridge extending W from the Atlantic. This system is producing mainly light to gentle anticyclonic flow and seas of 1-3 ft across much of the Gulf region. This pattern will change little over the next 48 hours. A surface trough will emerge off the Yucatan Peninsula each evening through Sat, enhancing nocturnal winds over the SW Gulf. CARIBBEAN SEA... Two tropical waves are moving across the Caribbean Sea. Please see the Tropical Waves section for details. A recent ASCAT pass provides observations of fresh to strong winds across the central Caribbean between 70W-75W. Fresh winds are noted over the eastern Caribbean, and gentle to moderate winds over the NW Caribbean, including the Yucatan Channel. Fresh to strong trades are expected across much of the area S of 18N and E of 83W through at least Fri. Winds will approach gale force near the coast of Colombia Thu night through Fri night. ATLANTIC OCEAN... As of 0300 UTC, a surface trough, reflection of an upper level cyclonic circulation, extends from 32N78W to 24N79W. Scattered showers and isolated tstms are observed ahead of the trough axis forecast to move west into Florida through tonight. An area of cloudiness and showers remains a few hundred miles southeast of Bermuda. Although this disturbance is currently disorganized, environmental conditions could become more conducive for a low pressure system to form by late this week in the area southwest of Bermuda. The system is then forecast to move generally northward over the weekend and begin interacting with a frontal system on Sunday, which would limit any additional development. Surface high pressure of 1032 mb located W of the Azores near 37N39W extends a ridge across the remainder of the central and eastern Atlantic forecast waters. Moderate to fresh trade winds are noted along the southern periphery of the ridge, which reaches the NE Caribbean. For additional information please visit http://www.hurricanes.gov/marine $$ MT